Your
best bet is to change them before 
you leave the country. The Next
best thing to do is change them for local bills and coins in the
next country on your itinerary. In most cases most coins will be
accepted for conversion as well as bills. In some cases smaller
coins will not be.
If
you expect to be returning to the country in the reasonably near
future you may wish to take the money home with you, especially
smaller change and smaller bills. We have baggies full of coins for
various countries in the 'travel' drawers of our dressers. The worst
thing you can do is bring the coins and bills home and expect easily
to exchange them. Unless you live in a major city you may find no
source to convert the money for you. And wherever you go you'll
rarely find anyone who will convert coins for you. If you are able
to find a place to do the conversion for you, expect to get a very
poor exchange rate (or high service charge.)
Most money exchangers
will only take paper money, plus you lose money every time you
exchange it because of commissions and the rate spreads. The trick
is to exchange only as much money as you are going to need in a
country. Try as you might, however, you will inevitably end up with
some small change leftover when you leave a country.
Some travelers save exactly what they will need for transportation
out of the country, then apply their remaining foreign currency to
their last hotel bill, charging the balance due. Others I know run
around at the train station or airport on their way out, wildly
spending the rest of their remaining cash. Others search out the
charity collection bins at many airports which are setup to relieve
foreign tourists of their "useless" change and put it to
good use at local charities.
Your best option, however, is to donate your leftover currency to
those in need (chances are, you
won't be using the coins for
anything more than novelty when you return, anyway). The United
States Fund for UNICEF has made it easy to turn your remaining
currency into charity with their Change
for Good program. To date, the program has raised over $31
million for needy children around the world. You can even donate old
currency that is no longer valid after the Euro conversion. You can also pick up
donation envelopes at Travelex
and Thomas
Cook locations across the country.
To donate your
leftover currency, mail it directly to:
Travelex America
Attn.: Jessica Lynch
Change for Good® for UNICEF
JFK Airport Terminal 4 IAT
Jamaica, NY 11430
